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    <title>Document</title>
    <script>
        // 利用函数求一到一百的和
        // 1.声明函数
        function getSum() {
            //2.函数体代码
            var sum = 0
            for (var i = 1; i <= 100; i++) {
                sum += i
            }
            console.log(sum);
        }
        // 3.调用函数
        getSum()//5050
        getSum()//5050 可以重复调用
    </script>
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